Sheet spreading and feeding apparatus



June 9, 1964 G. l. FREDHOLM 3,136,081

SHEET SPREADING AND FEEDING APPARATUS Filed March 26, 1962 9 Sheets-Sheet 1 June 9, 1964 e. l. FREDHOLM 3,136,031

SHEET SPREADING AND FEEDING APPARATUS Filed March 26, 1962 9 Sheets-Sheet 2 June 9, 1964 G. 1. FREDHOLM 3,136,081

SHEET SPREADING AND FEEDING APPARATUS Filed March 26, 1962 9 Sheets-Sheet 3 June 9, 1964 e. 1. FREDHOLM 3,136,081

' SHEET SPREADING AND FEEDING APPARATUS Filed March 26, 1962 9 Sheets-Sheet 4 I {so I 103 June 9, 1964 s. 1. FREDHOLM 3,135,081

SHEET SPREADING AND FEEDING APPARATUS Filed March 26, 1962 9 Sheets-Sheet 5 June 9, 1964 e. I. FREDHOLM 3,135,081

SHEET SPREADING AND FEEDING APPARATUS Filed March 26, 1962 9 Sheets-Sheet 6 Fig.5

June 9, 1964 G. l. FREDHOLM 3,136,081

SHEET SPREADING AND FEEDING APPARATUS Filed March 26, 1962 9 Sheets-Sheet 7 Fig.6

30 in h \\\l\ K g June 9, 1964 G. l. FREDHOLM SHEET SPREADING AND FEEDING APPARATUS 9 Sheets-Sheet 8 Filed March 26, 1962 June 9, 1 4 G. I. FREDHOLM 3,136,081

SHEET SPREADING AND FEEDING APPARATUS Filed March 26, 1962 9 Sheets-Sheet 9 United States Patent 3,136,081 SHEET SPREADING AND'FEEDING APPARATUS Gunnar Ivar Fredhoim, Forfattarvagen 44, Brornma, Sweden Filed Mar. 26, 1962, Ser. No. 182,562 Claims priority, application Sweden Mar. 27, 1961 4 Ciaims. (Cl. 38143) The present invention relates to apparatus for introducing a web of material into treatment apparatus. More particularly, the invention relates to apparatus for feeding laundry such as bed sheets, into a mangle.

In known devices difiiculty is encountered in trying to rapidly spread out the sheet onto a feeding table in front of the mangle, so that all the creases are removed and the sheet is introduced into the mangle with its front edge parallel to the roller of the mangle. Hitherto this operation has required the efforts of two persons, each of whom had to pick up a separate corner at one side of the sheet. This is diflicult to perform when the sheet is delivered in a creased state, because when the two corresponding corners of the sheet have been placed onto the feeding table, the front edge of the sheet must also be straightened and placed parallel to the mangle roller. In order to facilitate this step of the feeding operation it has been suggested to use a device associated with the feeding table of the mangle, in which device the stretched edge of the sheet is introduced and the sheet is then spread out and the creases removed by means of auxiliary means, so that it will reach the mangle roller in a straightened condition. Said device, into which the sheet is introduced, is in principle a clamping device extending parallel to the mangling' roller and arranged at the front part of the feeding table. After placing one edge of the sheet in the clamping device, the latter may be displaced a short distance in the direction of the feed, whereafter the clamping device is opened and the sheet placed onto the feeding table for further conveyance to the mangling roller. Said auxiliary means, which is used for spreading out the sheet on top of the feeding table, may consist of brushes for eliminating the creases, or a shaft-like chamber, into which the free end of the sheet is introduced in a straightened condition by the action of vacuum or compressed air. In this way a tedious manual operation is avoided, and the operators are free to operate the feeding-in of the next sheet. However, the feeding means just described does not eliminate the drawback of requiring two persons to operate the mangle.

The invention contemplates apparatus for spreading out and feeding a bed sheet to a mangle, and comprising clamping means into which a straightened edge of the web may be introduced, which clamping means is arranged to deposit the edge portion of the sheet onto a feeding table placed before the mangle and consisting of a belt conveyor or the like.

The main object of the invention is to provide a feeding device which can be operated by a single attendant while allowing the same working rate as the above mentioned known feeding devices.

In the accompanying drawings there is illustrated an embodiment of the invention.

FIG. 1 is a side elevation of the feeding device arranged in front of a mangle,

FIG. 2 is a front view of a portion of the device of FIG. 1,

FIG. 2A shows in entirety a front view of a portion of thedevice of FIG. 1 on an enlarged scale,

FIG. 3 is a vertical section.taken along lines 3-3 in FIG. 2, I

FIG. 4 is a plan view of a enlarged scale,

portion of the device on an "ice FIG. 5 is a side elevation partly in section of a clamping device on an enlarged scale in its open position,

FIG. 6 shows the clamping device of FIG. 5 in a closed position,

FIG. 7 is a longitudinal section of a conveyor on an enlarged scale for displacing nipping means from one side of the feeding table to the other side, and

FIG. 8 is a side elevation of the device shown in FIG. 7.

The feeding device according to the invention and illustrated in the drawings is suitable for the feeding of laundry, particularly bed sheets, into a mangle and requires only one person for operating it. In principle the feeding device consists of a pair of jaws or similar nipping means, which are displaceable by a driving device in a direction parallel to the mangle roller from one side of the feeding table to the other side thereof, and of a clamping device movable in the feeding direction of the mangle from a starting position in front of the feeding table, to a depositing position at the rear end of the feeding table, in which latter position the stretched sheet is placed upon the feeding table. The operator of the mangle need only put one corner of the sheet into the jaw, which will then move said corner While the operator guides the apertaining edge of the sheet with a slight retractive force, so that the sheet edge is stretched to a desirable extent. After the entire Width of the sheet has been brought over the feeding table, the opposite corner of the sheet is held fast by the operator and the clamping device is brought to embrace the edge thus stretched, for further conveyance thereof in the feeding direction and for placing the same upon the feeding table. During the feeding of the sheet into the mangle it is important that the sheet is spread out so that no creases are formed during the mangling. Auxiliary means particularly designed for this purpose form part of the feeding arrangement.

The feeding arrangement shown in FIGS. 1 and 2 comprises two side stands 1 arranged at opposite ends of the mangle and carrying a bar 2 displaceable in the feeding direction of the mangle. FIG. 1 shows the front part 3 of the mangle and the feeding table 4 which is made in a manner known per se and consists of a series of endless conveyor belts arranged one adjacent the other and running over rolls 5 and 6. The stands 1 are interconnected and braced. The cross bar 2 shown on a larger scale in FIGS. 5 and 6 is provided with two longitudinal guiding numbers 10 and 11 having opposed guiding edges 12 and 13, respectively forming guides for grooved pulleys 14 and 15. The said grooved pulleys are mounted on shafts, which are rigidly attached to a carriage 16, which can run along the bar 2 and be displaced from one end to the The jaws are displaceable along the bar 2 by means of pneumatic pressure means including a pneumatic cylinder 25 (FIG. 7) extending between the two side stands 1.

' In the cylinder is supported a piston 26 which is displace able back and forth in the cylinder by the pressure of air in the cylinder. The piston 26 and the carriage 16 are connected by a steel wire 27 (FIG. 4) running over two grooved wheels 28 arranged on the opposite stands 1. The cylinder 25 is provided with inlet valves for compressed air (not shown) at either end, the valves being operated by means of a pedal or other suitable controlmeans.

The bar 2 is provided with a clamping device 30, the clamping members of which extend along the whole length of the bar and comprise a rigidly mounted strip 31 of resilient material such as rubber, arranged along the guiding member 10, and a strip 32 also of resilient material, supported by a rail 33 which runs parallel to the strip 31 and is connected to arms 34 pivoted on a shaft 35. The arms 34 are freely rockable on the shaft 35 and are actuated by springs 36, FIG. 4, urging the strip 32 into contact with the strip 31. The strip 32 may be brought to an open position shown in FIG. by a rod 37 extending transverse to the arms 34 and attached to levers 38, rigidly fixed to the shaft 35. In FIG. 5 the rod 37 assumes an upper position in which it bears on a boss 39 on each of the arms 34. In addition, the rod 37 is adapted to actuate the member of the jaws 17 so that the same is opened when the arms 33 are swung down, the rod engaging an extension 40 of the member 20 of the jaws for this purpose. One end of the shaft 35 supports an actuating arm 41 (FIG. 3). Thus when the rod 37 is brought down, the arms 34 are free under the action of the springs 36 to rock counter clockwise, so as to bring the clamping device 30 to its closed position. When the rod 37 is lowered further, it engages the extension arm 40, thereby opening the jaws as shown by dash-dot lines 42, the spring 21 of the jaws passing its dead point, so that the spring holds the jaws in an open position, even if the rod 37 is raised again to the position shown in order to open the clamping device 30.

When a sheet is to be fed into the mangle, one of its corners is placed in the open jaws and the latter is closed by hand. The clamping device 30 is then open. After displacement of the carriage 16 along the bar 2 is completed the clamping device is closed so that the same clamps the stretched edge of the sheet and thereafter the jaws 17 are opened.

The bar 2 is movable in the direction of feed of the mangle and parallel to itself from the front position I i.e. the receiving position as shown in FIG. 3, backwards to a rear position II, shown in dash-dot lines. Said displacement takes place along rails 45 arranged one at either side stand. The bar is provided with end plates 46, on the outside of which belt pulleys 28 are mounted on bearing brackets 47, and also rolls 48, 49 are journalled on bolts 50. The rolls 48, 49 are arranged to run along the rails 45 while the bar is moving back and fourth between positions I and II, two rolls 48 resting on the upper face of the rail and one roll 49 on its bottom face. The displacement of the bar 2 is effected by a system of arms actuated by the compressed air cylinder 55. Piston rod 56 associated with cylinder is articulated to an arm 57 rigidly fixed to a tubular shaft 58, the ends of which are journalled in the side stands. Adjacent either stand is a plate 59 rigidly fixed to the tubular shaft in a position at right angles to the same. The plate carries four grooved pulleys 60 arranged in pairs and having grooves in engagement with opposite edges of arm 61, arm 61 is pivoted on a pin 62 which is attached to the end plate of the bar. Thus the arm 61 is guided between the pulleys for longitudinal displacement. The compressed air cylinder 55 is rockable about a pivot 63. When compressed air is introduced into the cylinder, the arm 57 swings clockwise, causing the tubular shaft 58 and the plate 59 to turn in the same d rection. The arm 61 is caused to shift its angular position, which results in the bar 2 being displaced from position I while the arm 61 is displaced in the guide device 59, 60. Position II constitutes a stop position for the bar, since the rails 45 are bent upwards thereat to form hooks 65, each catching one of the rolls 48 at opposite ends of the bar. The bar is simultaneously turned in a clockwise direction about its longitudinal axis owing to the bent portions 66 of the rails 45. During this motion the clamping device 30 is opened since the actuating mm 41 engages a guide cam 67 (FIG. 3), which is so shaped and arranged that the clamping device is opened just at the right moment for transferring the sheet onto the-feeding table 4 of the mangle. This process takes place at the end of the backward displacement of the bar, so that the sheet is brought into contact with the conveying belts of the feeding table while moving in the same direction as said belts. Owing to the tipping movement of the bar in position 11 the edge of the sheet will more easily slide from the strip 31 of the clamping device.

When the bar assumes its receiving position I the clamping device 30 is open and is maintained in this position by means of a compressed air cylinder 70, when the latter is supplied with compressed air. The piston rod 71 of the cylinder is articulated to an arm 72, which ivots about a pivot 73. A guide cam 74 is rigidly fixed to the arm 72, said cam engaging the actuating arm 41 when the piston rod 71 is in its upper end position to keep the arm in its lower position, which corresponds to the arms 38 and the rod 37 being in an upper position in which they keep the arms 34 raised, so that the clamping device 30 may receive the sheet.

Above the feeding table 4 there is arranged a roller 80, which is normally kept in engagement with the conveying belts of the feeding table. The roller is journalled in the ends of two arms 81, one at either side stand. The said arms 81 pivot about pivots 82 and are connected with a bell crank 83, which is in turn articulated to the piston rod 85 of a compressed air cylinder 84. The arm system is so arranged that the roller 80 moves away from the feeding table to an upper end position 86, indicated by dash-dot lines in FIG. 3, when compressed air is supplied to the cylinder 84. At the rear end of the feeding table a roller 87 rests on the conveying belts either under its own weight or under the action of a spring.

The clamping device 30 is brought into a closed or clamping position under the action of the springs 36 at the same moment as the cylinder 70 is emptied and the cam 74 releases the actuating arm 41. Simultaneously therewith an arm 90 rigidly fixed to the guide cam 74 rocks into engagement with a compressed air valve 91 arranged to supply compressed air to the cylinder 55, causing displacing of the bar 2 by means of the arm system 57, 61 from its position I to position II. While the bar is moving a compressed air valve 92 is actuated letting air into the cylinder 84 whereby the roller 80 is lifted from the feeding table so as to let the bar pass. Then the bar operates another valve 93 to discharge the air from cylinder 84, so that the roller by its own weight drops down onto the feeding table. Thereby the sheet is pressed against the conveying belts.

Above the path of the bar 2 an air box extends between the side stands 1 parallel to the bar. In the bottom 101 of said box there is a nozzle 102, which is arranged inside the box and extends along the entire length thereof. By means of the said nozzle it is possible to obtain an air screen with a downward direction of flow. Arranged straight beneath said nozzle is an air shaft 103, the orifice 104- of which is located on a slightly lower level than the bar 2 when the latter is in position 1. Arranged at the front edge of the shaft is a rotatable roll 105. A table 106 for supporting the laundry in front of the feeding apparatus merges into a plate 107 slanting upwards and extending to the lower portion of the roll 105, the rear side 108 of which is situated in the same vertical plane as the front wall 109 of the shaft 103. The bottom 110 of the shaft is flute-like and rounded. The said air box 1'80 and the shaft 103 form the above-mentioned auxiliary device, the purpose of which is to spread out and smooth the sheet before it is fed to the feeding table 4.

The shaft 103 communicates with the suction side of a fan (not shown) the pressure side of which may preferably be used for feeding the air box 100 with compressed air.

The described apparatus operates in the following manner.

The bar is brought to its position I with the clamping device 30 and the jaws 17 in their opened positions. The

jaws may be placed optionally to the extreme left or to the extreme right on the bar 2, i.e. at the right or the left side of the mangle. A corner of a sheet is placed in the jaws, which is then snapped into its closed position by hand. By operating a pedal or the like compressed air is supp ied to the cylinder 25, so that the jaws are displaced along the bar 2 carrying with it one corner of the sheet. When the jaws have been moved so far as to allow the straightened edge of the sheet to be placed onto the rubber strip 31 of the clamping device 30, air is discharged from the cylinder 70 by means of an outlet valve which may be operated from either side of the feeding arrangement. In this way the clamping device is brought into a closed position by spring action and clamps the straightened edge of the sheet. In a following step the bar 3'7 opens the jaws. When emptying the cylinder. 70 the valve 91 is actuated and compressed air is supplied to the cylinder 55, so that the bar is displaced towardsits rear position II. During the latter passage of bar 2 the free portion of the sheet is blown down into the shaft 193, whereby creases are straightened out. The roller 88 is lifted from the feeding table, whenthe bar acts upon the valve $2, the bar then passing this point on its way rearwards towards and into position II, whereafter the roller 8t drops down to engage the conveyed sheet. During the last part of the motion of the bar, the clamping device $6? is opened by the engagement of the arm 41 with the guide cam 67, the bar at the same time undergoing a tipping movement to deposit the edge of the sheet onto the feeding table. When the bar has stopped in its end position II a delaying mechanism (not shown) is actuated whereby the bar as held in its position II until the front edge of the sheet has been caught by the roller 557. Then the delaying device causes the supply of compressed air to the cylinder 55 to return the bar to its initial position I. During the return movement the valve 93 is operated to admit compressed air into the cylinder $4, the roller 89 being for a moment lifted from the feeding table to let the bar pass. During the motion of the bar to its position I, the jaws 17 may be displaced along the bar to its initial position by means of the piston 61 of'the cylinder 25. After the bar has reached its end position I compressed air is supplied to the cylinder 70, the clamping device 30, which was brought into its closed position after the bar had left its position II, hence being opened again. Thus the initial position is attained and the bar is ready for a new feeding operation.

While the invention has been described with respect to a preferred embodiment, it will be apparent for those skilled in the art to make modifications and variations ing from the spirit of the invention as defined in the following claims.

What I claim is: v 1. In combination with a feeding table for feeding a sheet to a mangle, clamping means movably supported with respect to the feeding table and operative between open and closed positions for releasably engaging the wvith respect to the preferred embodiment without departmeans for movement parallel thereto and adapted to engage a single corner of the sheet which is inserted through the open clamping means, means for displacing the jaw means, with the corner of the sheet engaged therein, in a direction parallel to the clamping means with the latter open and operating means for sequentially actuating the jaw means and the clamping means in order to first close the clamping means and thereby secure the entire edge of the sheet and then open the jaw means to free said corner of the sheet.

2. The combination as claimed in claim 1 comprising spring means urging the clamping means to a closed 7 position, the operating means being effective to hold said clamping means open and to allow the same to close under the action of said spring means as said operating means prepares to open the jaw means, said clamping means being operative to close and clamp the edge of a sheet before the latter is released by the jaw means.

3. The combination as claimed in claim 1 wherein the jaw means comprises a pair of jaws and a snap spring engaging said jaws, said jaws'being maintained selectively in closed and open position by said snap spring.

4. In combination with a feeding table for feeding a sheet to a mangle, jaw means for engaging a single corher of the sheet, means for displacing the jaw means transverse to the feeding table whereby by holding another corner of the sheet an edge of the sheet may be placed parallel to the feeding table, clamping means extending parallel to the feeding table for engaging said sheet along the entire aforementioned edge thereof, means for operating said clamping means to engage the edge of the sheet and thereafter open the jaw means and means for advancing said clamping means with the edge of the sheet secured therein to a position over the feeding table whereat the clamping means is opened to deposit the edge of the sheet onto the feeding table, said clamping means being located behind said jaw means relative to the direction of movement of the clamping means towards the feeding table, said jaw means'being' accessible through said clamping means with the latter open whereby the edge of the sheet is firstly introduced through the clamping means before the edge is engaged in the jaw means. i I

References Cited in the file'of this patent UNITED STATES PATENTS Sweden Feb. 2, 

1. IN COMBINATION WITH A FEEDING TABLE FOR FEEDING A SHEET TO A MANGLE, CLAMPING MEANS MOVABLY SUPPORTED WITH RESPECT TO THE FEEDING TABLE AND OPERATIVE BETWEEN OPEN AND CLOSED POSITIONS FOR RELEASABLY ENGAGING THE ENTIRE EDGE OF A SHEET FOR TRANSFERRING THE SAME TO THE FEEDING TABLE, JAW MEANS SUPPORTED BEHIND THE CLAMPING MEANS FOR MOVEMENT PARALLEL THERETO AND ADAPTED TO ENGAGE A SINGLE CORNER OF THE SHEET WHICH IS INSERTED THROUGH THE OPEN CLAMPING MEANS, MEANS FOR SEQUENTIALLY ACTUATING MEANS, WITH THE CORNER OF THE SHEET ENGAGED THEREIN, IN A DIRECTION PARALLEL TO THE CLAMPING MEANS WITH THE LATTER OPEN AND OPERATING MEANS FOR SEQUENTIALLY ACTUATING THE JAW MEANS AND THE CLAMPING MEANS IN ORDER TO FIRST CLOSE THE CLAMPING MEANS AND THEREBY SECURE THE ENTIRE EDGE OF THE SHEET AND THEN OPEN THE JAW MEANS TO FREE SAID CORNER OF THE SHEET. 